Generalized coherent states and uncertainty relations in $\mathcal{P}\mathcal{T}$-symmetric position dependent mass systems

Pinaki Patra

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arXiv · 2208.10336

Generalized coherent states and uncertainty relations in $\mathcal{P}\mathcal{T}$-symmetric position dependent mass systems

Pinaki Patra

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Abstract

In this paper, we investigate a class of PT-symmetric quantum systems with position-dependent effective mass (PDEM). We factorize the PDEM Hamiltonian using a pair of generalized annihilation and creation operators. The resulting commutation relation introduces the notion of a position-dependent effective Planck parameter, which reduces to Planck's constant in the conventional Hermitian quantum system with constant mass. These generalized ladder operators define a deformed phase space, within which we construct a generalized Gaussian state to first order in the PT-symmetry parameter. We then revisit the Heisenberg uncertainty principle for this state and demonstrate that the deformed position and momentum operators satisfy the corresponding uncertainty relation in the PT-symmetric PDEM framework. Finally, we present explicit computational results for a toy-model oscillator with position-dependent effective mass in a PT-symmetric setting. In the conclusions section, we outline a gedankenexperiment for experimental determination of $PT-symmetric parameter.

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Pinaki Patra. 2022-08-19. Generalized coherent states and uncertainty relations in $\mathcal{P}\mathcal{T}$-symmetric position dependent mass systems. https://arxiv.org/abs/2208.10336

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